Handling edge cases of new login screen

chrome/browser/resources/chromeos/login/md_header_bar.js

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 /**
  * @fileoverview Login UI header bar implementation.
  */
 
 cr.define('login', function() {
   /**
@@ skipping 110 matching lines @@
      * Whether action box button is in active state.
      * @type {boolean}
      */
     get isMoreSettingsActive() {
       return this.getMoreSettingsMenu.classList.contains('active');
     },
     set isMoreSettingsActive(active) {
       if (active == this.isMoreSettingsActive)
         return;
       this.getMoreSettingsMenu.classList.toggle('active', active);
-      $('more-settings-button').tabIndex = active ? -1 : 0;
+      $('more-settings-button').tabIndex = active ? -1 : 4;
     },
 
     /**
      * Add user button click handler.
      *
      * @private
      */
     handleAddUserClick_: function(e) {
       Oobe.showSigninUI();
       // Prevent further propagation of click event. Otherwise, the click event
@@ skipping 314 matching lines @@
    * Convenience wrapper of animateIn.
    */
   HeaderBar.animateIn = function(fast, callback) {
     $('login-header-bar').animateIn(fast, callback);
   };
 
   return {
     HeaderBar: HeaderBar
   };
 });